<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Title</title>
</head>
<body>
<!--
  v-if
  v-else
  v-else-if
  v-show
-->

<div id="app">
  <div v-if="score>=90">优秀</div>
  <div v-else-if="score>=80">良好</div>
  <div v-else-if="score>=60">一般</div>
  <div v-else>不及格</div>
</div>

<script src="../lib/vue.js"></script>
<script>
  let vm = new Vue({
    el: '#app',
    data: {
      score: 90
    }
  })
</script>

</body>
</html>